Many works of fiction represent real-life legal issues poorly, and sometimes with interpretations that are downright ridiculous.
Examples can be found at the TVTropes link on "Artistic License - Law".
Are questions about the (correct or incorrect) usage and application of law in such works on-topic?
I tend to agree with nomen agentis's comment - questions about the application of law to, or within, fictional works, are likely on topic, as per Are hypothetical application of the law questions on topic? - it's just that these hypotheticals happen to be inspired by, or based in fictional works. I'll just add the caveat that you'll need to provide a real-world jurisdiction to such questions; if you want to know about the law in a non-existent place, we can only do it by reference to existing law.
I think I've asked one myself, actually - Could an employee be fired as they are about to quit in order to pay them severance? is inspired by The Office.
From another viewpoint, I would say that debunking or affirming various (mis)representations of the legal system as portrayed in fictional works — books, television, film — is probably a good thing and would be a great way to make the internet a better place.
This is not only on topic, we have a specific tag for it: law-in-fiction. At the moment, there are 34 questions so tagged. I have asked several and answered some others. The most recent one I have asked is Is a will provision naming "my wife" as a beneficiary before marriage valid? and I have posted an answer to Is it true that it's not illegal for a parent to sell their 13-year-old child to a drug dealer?
When the fiction is set in a time significantly distant from the current one, and particularly when it is set in an imaginary society with its own law, questions may have to be answered based on current or historical law, unless the fictional work details the law in the imagined setting sufficiently to base an answer on (which it usually does not).
